This invention claims priority from Japanese Patent Application Number JP 2007-050583 filed on Feb. 28, 2007, the content of which is incorporated herein by reference in its entirety.
1. Field of the Invention
The present invention relates to a semiconductor device.
2. Description of the Related Art
A semiconductor device using a lead frame generally includes an island, a plurality of leads whose one ends are disposed around the island, and a semiconductor chip provided on the island. Moreover, a bonding pad of the semiconductor chip and the one ends of the leads are connected to each other by use of thin metal wires. This technology is described for instance in Japanese Patent Application Publication No. 2007-5569. Furthermore, the island, the plurality of leads, the semiconductor chip and the plurality of thin metal wires are sealed by an insulating resin so as to expose the other ends of the plurality of leads. Here, in the plurality of leads, portions sealed by the insulating resin are called inner leads, and portions exposed from the insulating resin are called outer leads. By bending the outer leads according to need, the other ends of the leads are mounted on a printed board or the like by use of solder and the like.
Moreover, a stack type semiconductor device is also realized, which is formed by stacking a plurality of chips on an island. In this semiconductor device, a child chip smaller than a parent chip is stacked on the parent chip, and both of the parent chip and the child chip are electrically connected by use of thin metal wires.
The semiconductor device as described above can be miniaturized by a recent high technology. However, a surface of the child chip is disposed at a position higher than that of a surface of the parent chip from a surface of the island. Accordingly, when the child chip is further connected by use of the thin metal wire, a top of the thin metal wire is positioned higher. Consequently, there is a problem that a thickness of the semiconductor device, in other words, a thickness of a package is increased.